As a special light source, ultraviolet (UV) light is widely used in all aspects of social production and life. UV light is electromagnetic radiation whose wavelength is shorter than that of visible light but longer than that of X-ray, the wavelength range is 10 nanometers (nm) to 400 nanometers and the energy range is 3-124 eV. It is named because the frequency of electromagnetic waves in the spectrum is higher than that of purple visible to the naked eyes, which is also commonly known as ultraviolet light.
UV light is mainly divided into the following 3 categories according to different biological effects:
- Near ultraviolet (UVA): Longwave Ultraviolet light A with a wavelength of 315~400 nanometers.
- Middle ultraviolet (UVB): Medium wave Ultraviolet light B with a wavelength of 280~315 nanometers will be absorbed by the ozone in the stratosphere.
- Deep ultraviolet (UVC): Short-wave Ultraviolet light C, with a wavelength of 100~280 nanometers, has the weakest UVC penetration ability and cannot penetrate most transparent glass and plastic. The deep ultraviolet light contained in sunlight is almost completely absorbed by the ozone layer and will not reach the earth's surface.
Traditional ultraviolet light emits ultraviolet by exciting inert gas in the ultraviolet lamp tube through voltage. Ultraviolet LED is a solid-state light-emitting device that uses a particular chip component to emit ultraviolet light with a particular wavelength during the PN junction electron hole light-emitting process. Its ultraviolet wavelength is usually in the range of 200-400 nm. According to different wavelengths emitted by UV LEDs, they can be divided into UVA-LED (315~400nm), UVB-LED (280~315nm) and UVC-LED (200-280nm).